The present invention exploits principles discovered by the inventors in investigating the gyroscopic response of a femtosecond ring dye laser operating on a rotating platform. The investigation was carried out at the University of New Mexico Physics and Astronomy Department. Expected advantages of a mode-locked laser gyro over a conventional CW laser gyro include smaller coupling between the two counterpropagating waves and the absence of mode competition in a homogeneously broadened gain medium. Both features are a result of the fact that the two counterpropagating pulses in a passively mode-locked laser cavity only meet at two points, both outside of the gain medium. However, in a passively mode-locked laser, a strong coupling between two counterpropagating waves establishes the crossing point between the two pulses. It is therefore logical to expect that this same coupling may result in a lock-in of the gyro response.
It is well known in the art that a propagating light pulse will experience a path length that is proportionate to the index of refraction of the optical medium in which it is traveling. The present invention exploits this phenomenon to avoid a lock-in of the gyro response.
It is therefore a motive of the invention to avoid the lock-in of a laser gyro using a resonant cavity dither with index of refraction modulator.